Micron MotoGP Exhaust

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I'm getting rid of my bandit 12 and going for a CBR125 (or XTC125/YZF125). A two stroke 125 is out of the question, as I absolutely hate RS125's, they're the most awful uncomfortable bikes I've ever been on, and cannot for the life of me find another RG125 or even a Derbi GPR125.

It seems like I have much more fun the smaller the engine size.

But I have an idea as to how I can get around 24-26bhp out of a 4 stroke 125

Going for a big bore kit, 4 valve head,full exhaust system, might get it to around 16-18bhp and anything I can do to reduce weight (if that is actually possible on a 125 and I weigh 10 stone @ 5'5" , so there's not much I can do there :p) but this brain storm came to me.

Once I get the actual bike I'll be putting the build on the net. (assuming I just don't end up wasting a whole load of money and have seriously screwed up the theory.)

The thing is, I can't use the power of the Bandit 12, as I'm afraid of killing myself, and the 636 was just no fun what so ever, but I had no/little fear on my 50 or any of the 125's (even though I crashed them several times).
 
Soldato
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Surely though, if you want 25bhp, why not go for a larger, more powerful bike? You will save some money in the process and remove the hassle of having to make the modifications.

People forget that 125cc bikes carry a high demand and for what they are, they are pretty expensive. Especially when you think that I couldve got a CB500 for less than I am paying for the CBR125. The only problem is that I dont yet have a full license so have no choice.

I would certainly prefer a CB500, over any 125cc bike, mainly due to its extra horsepower, allowing me to carry items/luggage without any problem.
 
Associate
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i disagree man, i was looking at them up at three cross mc, and it looked awesome even with a row of R6s next to it... i know everything is smaller, but it's real nice styling for a little bike :)

hmm, another thing is, inevitably your gonna get chavs trying to race you thinking its a missile which is just going to lead to major embarrassment!
 
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I'm getting rid of my bandit 12 and going for a CBR125 (or XTC125/YZF125). A two stroke 125 is out of the question, as I absolutely hate RS125's, they're the most awful uncomfortable bikes I've ever been on, and cannot for the life of me find another RG125 or even a Derbi GPR125.

It seems like I have much more fun the smaller the engine size.

But I have an idea as to how I can get around 24-26bhp out of a 4 stroke 125

Going for a big bore kit, 4 valve head,full exhaust system, might get it to around 16-18bhp and anything I can do to reduce weight (if that is actually possible on a 125 and I weigh 10 stone @ 5'5" , so there's not much I can do there :p) but this brain storm came to me.

Once I get the actual bike I'll be putting the build on the net. (assuming I just don't end up wasting a whole load of money and have seriously screwed up the theory.)

The thing is, I can't use the power of the Bandit 12, as I'm afraid of killing myself, and the 636 was just no fun what so ever, but I had no/little fear on my 50 or any of the 125's (even though I crashed them several times).

Isn't fear one of the things that makes biking fun ?... a bandit 12 is plenty usable surely and relatively tame by bike standards, just pin the throttle and enjoy :)

A 636 not fun ? :confused:

I hate to say if you really thinking of a 125 instead of your past bikes then biking maybe aint for you :(, im not sure anyone could live with a 125 on a daily basis after owning the machines you have.
 
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Associate
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Isn't fear one of the things that makes biking fun ?... a bandit 12 is plenty usable surely and relatively tame by bike standards, just pin the throttle and enjoy :)

A 636 not fun ? :confused:

I hate to say if you really thinking of a 125 instead of your past bikes then biking maybe aint for you :(, im not sure anyone could live with a 125 on a daily basis after owning the machines you have.

I absolutely hate cars, they're a pain to work on and I will never own one, or do the test.

My dad has a 1098S and I found it completely lame, it seemed so dead (not slow, just no "soul"). I went for the kawasaki because it was unique, with the colours and the way I modded it, but it was a waste of power because I was afraid of it spinning out on me going around corners (read as not confident/cowardly) I sold it and bought the B12, because I wanted straight line power, but it was even slower than 636, but at least it was mega comfortable.

Realistically the B12 has to go because it's in such a bad shape it won't pass MOT and I don't want to spend money on it, when I could just add another couple of hundred to the repairs and get a good 125.

Plus I always had fun racing other 125's on an underpowered bike. It fairly shuts up the aprilia fan boys when they get beat by 50's or 4t 125's

Maybe I should try and find a GSX/ZXR400R; Or even better an RGV250.
 
Soldato
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Plus I always had fun racing other 125's on an underpowered bike. It fairly shuts up the aprilia fan boys when they get beat by 50's or 4t 125's

Aaaah. So you are skillfull rider. You are effectively handicapping yourself when taking on the faster bikes.

I've only just started motorcycling and I hope to be able to have the skill to pull of traffic lights and be able to beat those on more powerful bikes. Of course, I won't use that skill on traffic lights as I feel its a little silly.

Anyway gents, I've just returned from buying the bike. I rode it from East London to North West London.

The verdict:
Regarding the exhaust: its VERY quiet, which is probably as result of having the baffle in tact.

Performance:
0-40mph: The bike accelerates fairly quickly to 40mph.
40-50mph: Acceleration to 50mph is a bit laboured.
50-60mph: Once you hit 50 mph acceleration is very laboured, though I was using 6th gear. Apparently on the cbr125, its recommended to use 5th gear and use 6th only when you are going downhill and are hugging the fuel tank (aerodynamics).

I'm still learning how to ride a bike, as I have only just passed my CBT and I'm learning that the CBR125 has a very clunky 1st to 2nd gear change. After that, its smooth.

One thing of note, regarding speed limits: I was on the dual carriageway for a long time and I was observing speed limits strictly, however, I was finding A LOT of people zipping by me in cars. If my speedometer is anywhere near accurate, I know for a fact that many cars were breaking the speedlimit.

I can certainly see why people would want something more powerful, but I can see people breaking speed limits, fairly easy with faster bikes, without even realising and as a result getting license points and fines.

EDIT: I also wanted to add that after squeezing the throttle tight, continuously my forearm is aching. Is there a technique that I'm missing here?
 
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TBH, if it was me and I wanted a small capacity bike with decent(ish) power, then I'd either look at a 400cc import or mebbe even the Kwak ZX250R that has not long been released.
I would love another RGV250 though, but you pay through the pants for them.
 
Soldato
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Looking at getting on of these for my first bike, with a few others in the frame, might buy it new but I dunno yet.

Don't buy it new. It just isnt worth it.

This is my first bike and I've only ridden it for a little while and I can already see that it is a bike used purely to gain practise/experience/confidence on, whereafter you take your full bike test and buy a more beefier bike.

...and this coming from someone who doesn't believe in breaking speed limits.

The only thing that makes me feel good about this purchase is that I feel I got a good deal and that it serves its purpose. I would be gutted if I had paid £2500 (or whatever it is new), knowing that in 6-12 months I would take my full test and sell this for around £1000 less.
 
Soldato
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I would be gutted if I had paid £2500 (or whatever it is new), knowing that in 6-12 months I would take my full test and sell this for around £1000 less.

It's £3,070 new. Just looking at buying new because it's easier, as a private seller would have to be nearby as I wouldn't be able to go so far to pick it up, and I couldn't drive it on motorways.

The only other option is a used dealer who delivers for a decent price, but I'm abit adverse to not actually seeing it before I buy it and having a chance to inspect as such.
 
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In ** bottom drawer...
Aaaah. So you are skillfull rider. You are effectively handicapping yourself when taking on the faster bikes.

I've only just started motorcycling and I hope to be able to have the skill to pull of traffic lights and be able to beat those on more powerful bikes. Of course, I won't use that skill on traffic lights as I feel its a little silly.

Anyway gents, I've just returned from buying the bike. I rode it from East London to North West London.

The verdict:
Regarding the exhaust: its VERY quiet, which is probably as result of having the baffle in tact.

Performance:
0-40mph: The bike accelerates fairly quickly to 40mph.
40-50mph: Acceleration to 50mph is a bit laboured.
50-60mph: Once you hit 50 mph acceleration is very laboured, though I was using 6th gear. Apparently on the cbr125, its recommended to use 5th gear and use 6th only when you are going downhill and are hugging the fuel tank (aerodynamics).

I'm still learning how to ride a bike, as I have only just passed my CBT and I'm learning that the CBR125 has a very clunky 1st to 2nd gear change. After that, its smooth.

One thing of note, regarding speed limits: I was on the dual carriageway for a long time and I was observing speed limits strictly, however, I was finding A LOT of people zipping by me in cars. If my speedometer is anywhere near accurate, I know for a fact that many cars were breaking the speedlimit.

I can certainly see why people would want something more powerful, but I can see people breaking speed limits, fairly easy with faster bikes, without even realising and as a result getting license points and fines.

EDIT: I also wanted to add that after squeezing the throttle tight, continuously my forearm is aching. Is there a technique that I'm missing here?

Hey there.

The 125 CBRs are great little bikes if you take the at face value and know its a 15bhp machine with performance to match.Ive had mine for 2 months now and really enjoy comuting on it...as to riding out of town(North London to Surrey to see mates...) it does labour at NSL, but riding confidently generally means I dont get bullied by trucks/cars on the bigger roads.
As to the throttle/forearm ache, try and relax, its quite a weak spring in the throttle and doesnt need a load of iron gripping to keep it "pinned", well in my oppinion anyway.
I adjusted the angle to the clutch and brake lever to point down more and that made a difference to comfort. As most new things it just takes time to adjust your body to it.

I guess as Ive been driving for 20 years now and cycling for longer on the roads I knew the power wouldnt be enough for long so am doing my theory on 5th may and full test shortly after with a view to getting a CBR 600 RR as my daily ride.
The bigger bikes feel so much more stable on open roads and the power is reassuring, just because its there doesnt mean you HAVE to use it!

Anyway, hope you enjoy the bike and commuting.

- Perry.
 
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Performance:
0-40mph: The bike accelerates fairly quickly to 40mph.
40-50mph: Acceleration to 50mph is a bit laboured.
50-60mph: Once you hit 50 mph acceleration is very laboured, though I was using 6th gear. Apparently on the cbr125, its recommended to use 5th gear and use 6th only when you are going downhill and are hugging the fuel tank (aerodynamics).

...

I'm still learning how to ride a bike, as I have only just passed my CBT and I'm learning that the CBR125 has a very clunky 1st to 2nd gear change. After that, its smooth.

...

EDIT: I also wanted to add that after squeezing the throttle tight, continuously my forearm is aching. Is there a technique that I'm missing here?

I wouldn't pay attention to when people are telling you to change gears. Use them as you see fit. If you're lacking power then knock it down a gear or two. Similarly if it begins to get too high up the rev range then shift up. Listen to the bike over other people.

The change from 1st to 2nd can be quite clunky due to the box having to pass through neutral. Nothing to be concerned about.

You do not need to squeeze the throttle at all because it requires only a small amount of weight for it to stay in position. Ideally you should be loose on the bike at all times (including your hands, arms and legs).

When you are more comfortable with the bike you could start to do clutchless shifts which, if done correctly, provide a much smoother and quicker gear change than one using the clutch.
 
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Soldato
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12 Feb 2004
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Manchester
i had a cbr125 and i had no confidence in overtaking what so ever

got me a Bandit 600 now and its pretty awesome! (for a biker noob like me)
 
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Soldato
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When you are more comfortable with the bike you could start to do clutch-less shifts which, if done correctly, provide a much smoother and quicker gear change than one using the clutch.

I actually heard that clutchless shifts could damage the gear box/shift mechanism, otherwise, for me, a semi-automatic gear box (ie. clutchless shift), is certainly the way forward.

Some Ferrari cars have the semi automatic gearboxes where they have paddles behind the steering wheels - something copied from F1. For me semi automatic gearboxes on cars and motorbikes are the way forward.

Do you have any tips on clutchless gear shifts?
 
Man of Honour
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Christchurch UK
throttle back slightly while applying pressure on pedal and it will 'fall' into next gear...

get it wrong and it will feel really notchy, done right it's more efficient than a clutch shift ever could be...

some bikes gearboxes do it better than others.. and some will only do it nice at certain revs, just experiment and find out how your bike 'likes it' done :) (generally the higher the revs your bike is at the easier it will do it, so slow speed shifting to 6th may be notchy)

never do clutchless downshifts as the wheel would then drag the engine and cause a possible lock up and skid / off
 
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